Recently, liquid crystal displays (LCDs) have become the main stream in the flat display area. The LCDs use the principle that the alignment of liquid crystal molecules can be controlled with externally applied electric field due to the dielectric anisotropy and conductive anisotropy of the liquid crystal molecules, so that the liquid crystal thin film can give rise to various photoelectric effects.
The panel of a typical thin film transistor liquid crystal display (TFT-LCD) comprises a TFT array substrate and color filter substrate arranged in parallel to each other. Spacers are interposed between the two substrates to provide a space for filling liquid crystal between the two substrates, and the peripheral areas around the display area of the two substrates are bonded together with adhesive so as to obtain a liquid crystal cell of the liquid crystal display.
The spacers may be ball spacers that are distributed, for example, on the color filter substrate, or may be column spacers that formed, for example, on the color filter substrate by a photolithographic method. In the photolithographic method, photo resist is coated on the color filter substrate and then exposed with a mask and developed to obtain the column spacers.
When a LCD operates in a high temperature, the liquid crystal molecules may be displaced with gravity field, causing gravity mura phenomenon and degrading display quality of the LCD. Mura phenomenon refers to partially or entirely non-uniform chrominance in the image displayed by the LCD.
Furthermore, during the course that liquid crystal is filled into a liquid crystal cell in manufacturing, if the liquid crystal builds up excessively in the peripheral areas, it may lead to peripheral mura phenomenon, and in the worse case large-area light leakage may occur in lower portion of the LCD.